Research Of United Toxicity Of Formaldehyde And Xylol To The Genetic Toxicity And Mechanism Of Mice

Objective:Indoor over decoration or the use of inferior building decoration material heavily aggravated room air pollution. Both formaldehyde and xylol are volatile organic compound, and commonly coexist in multiple pollution source, and are the major pollutants of our indoor environment. The two are not only in the high level pollution, but also big biological toxicity. They have mutagenicity and their hazard to health attracts universal attention day by day. At present, there is not much research on the united toxicity of formaldehyde and xylol and even less report on the united effect research of genetic toxicity. Through the injection toxicity test of single and untied abdominal cavity with formaldehyde and xylol, the study probe into the united toxicity of formaldehyde and xylol to the genetic toxicity and mechanism of mice to provide basis for preventive treatment of influence of indoor decoration pollution to human health.Methods:78health and clean Kunming mice (bisexual each half) at18-22g was selected and divided into13groups randomly. In which, there are low dosage (5mg/kg), medium dosage (10mg/kg), and high dosage (20mg/kg) formaldehyde toxicity and normal saline control group; low dosage (50mg/kg), medium dosage (100mg/kg), and high dosage (150mg/kg) xylol toxicity and peanut oil control group; low dosage (2.5mg/kg formaldehyde+25mg/kg xylol), medium dosage (5mg/kg formaldehyde+50mg/kg xylol), and high dosage (10mg/kg formaldehyde+75mg/kg xylol)) united toxicity group and normal saline+peanut oil (volume ratio1:1) control group; cyclophosphamide (40mg/kg) as positive nuclear test control group. Six mice in each group with bisexual each half. The test used injection toxicity to left and right abdomen of mice with10ml/kg once a day for seven days. After finished toxicity, the test use10%chloral hydrate to narcotize mice and pour normal saline into their heart to fully discharge internal blood of mice and promptly take out femur marrow, liver and kidney. Observe of DNA damage of marrow cell and inspect of cell凋亡condition to test the content of Superoxide dismutase, Maleic dialdehyde and Glutathione in liver and kidney, and DNA-protein crosslinks coefficient.Results:1. Toxicity effect of formaldehyde and xylol to mice marrow cell:(1) both formaldehyde and xylol toxicity group had caused the increase of marrow cell micro nuclear rate (P<0.05), and micro nuclear rate went up with the increase of toxicity dosage; micro nuclear rate of formaldehyde and xylol united toxicity group was higher than single toxicity group, which is especially obvious in high dosage united toxicity group (P<0.05).(2) Both formaldehyde and xylol toxicity group could increase DNA content of mice marrow comet cell stern and tail moment, and which is especially obvious in high dosage group (P<0.05); DNA content of mice marrow comet cell stern and tail moment increased in the low dosage united toxicity group was already higher than the single formaldehyde and xylol toxicity group (P<0.05); With the increase of toxicity dosage, united toxicity action went up obviously.(3) With the increase of toxicity dosage, the cell凋亡rate of each formaldehyde and xylol group tend to increase, and which was especially obvious in high dosage group; compared to single formaldehyde and xylol toxicity, marrow cell凋亡rate of different dosage united toxicity groups were all higher.2. Genetic toxicity action of formaldehyde and xylol to mice liver:(1) Mice liver SOD and GSH content of each formaldehyde toxicity group are lower than that in control group and MDA content are higher than that in control group (P<0.05); Xylol toxicity had the same damage to mice liver as formaldehyde toxicity, but the toxicity is lower; united toxicity of the two had some certain of coordination effect to the oxidization damage of mice liver and the formation of MDA.(2) DPC coefficient of mice liver in formaldehyde toxicity group was higher than that in control group (P<0.05); With the dosage increase of xylol, DPC coefficient of mice liver tended to increase; compared to single formaldehyde and xylol toxicity at same dosage, DPC coefficient of mice liver in united toxicity group was higher (P<0.05). There is chance of coordination toxicity action.3. Toxicity action of formaldehyde and xylol to mice kidney:(1) MDA content of each formaldehyde toxicity group are higher than that in control group(P<0.05); and it would went up with the increase of toxicity dosage; SOD and GSH content are lower than that in control group. Compared to single formaldehyde and xylol toxicity at same dosage, SOD and GSH content of kidney in united toxicity group decreased obviously; and MDA content increased obviously (P<0.05).(2) Formaldehyde and xylol toxicity could increase the DPC content of mice kidney P<0.05); Compared to single formaldehyde and xylol toxicity at same dosage, DPC coefficient of kidney in united toxicity group went up obviously (P<0.05). There is chance of coordination toxicity action.Conclusion:Both formaldehyde and xylol can cause the increase of mice marrow cell micro nuclear rate and cell凋亡,and have damage action to DNA. They can also cause peroxidation damage to mice liver and kidney lipid and arouse DPC effect of liver and kidney cell; united toxicity of formaldehyde and xylol aggravate the genetic damage of mice marrow, liver and kidney. There is a certain coordination action. Chromosome breakage, DNA damage, cell凋亡,lipid peroxidation damage are all possible the important mechanism of mice genetic toxicity caused by formaldehyde and xylol.